There are two main options to get Satellite TV, Dish and DirecTV.
Dish is typically better for RV use for two major reasons. The first is it is easier to get a self aligning antenna that still receives HD signal. These units are the Tailgater and Playmaker. The other is they make specific plans that are month to month and require no contract. You can easily suspend if you are not traveling for 6 months of the year, or even just cancel at anytime. Also, if you have Dish at home already you can use the the Dish Anywhere app for free, or add a box for only $7/month.
DirecTV is a suitable option for RVs if you are fulltime stationary. Example a seasonal site or living in it full time. You can get a self Aligning antenna that gets HD but they require a professional install are much more expensive. If you have DirecTV at home you can add a box to your account for only $7/month.
There are also two main options for streaming TV solutions
SlingTV is the industry leader in streaming live tv. They have a couple packages to choose from to get the best programming for your needs. A couple of huge advantages are the ability to integrate local channels into the same guide with the AirTV player, and the ability to adjust the video quality to best suite the internet connection you are working with.
DirecTV NOW offers some of the best the introductory offers in streaming tv. They have some great promotions to get you started and with no contracts you can always explore other options down the road if it doesn't work for you!